判断题 The back-chaining technique means the students repeat a sentence after the teacher, starting from the end part of the sentence and moving towards the beginning.（）

判断题 A phoneme is the smallest distinctive sound unit, incapable of change in different phonetic environments.（）

判断题 Consonants vary depending on where and how the air stream gets through, the place and movement of the tongue, and also whether the voice is used or not.（）